The present invention relates to a connector which is installed in an opening portion of a container in which a liquid such as semiconductor high purity chemicals or general chemicals is stored.
Generally, semiconductor high purity chemicals and general chemicals are stored in a container having sufficient resistance to these chemicals.
Heretofore, as shown in FIG. 6, two opening portions 1a are formed in this container 1, and plugs 3 provided with plug portions 2 are fitted in these openings 1a. A siphon tube 4 which extends to near the bottom of the container 1 is connected to one of the plugs 3.
Then, to draw the liquid stored in the container 1, firstly, a socket 6 connected with a hose 5 is connected to the plug portion 2 of the plug 3 provided in the opening portion 1a of the container 1, and the liquid inside the container 1 is delivered to the hose 5 via the siphon tube 4 by a pump P.
At this time, so that the container 1 interior does not become a negative pressure, inert gas is fed in from a hose 5 connected to the plug 3 on the other side.
Furthermore, completely taking out all the liquid from the inside of the container 1 to make it empty is performed by detecting the presence of an outflow of gas on the side drawing the liquid. Then, when an outflow of gas is detected, it is judged that the container 1 interior is empty, and this empty container 1 is changed for a new container 1 with liquid stored therein.
Incidentally, the siphon tube 4 that takes out the liquid from inside the container 1 has an external thread comprising a taper thread formed on an upper end thereof, and is connected by wrapping a seal tape around this external thread and screwing into an internal thread comprising a taper thread formed on the plug 3 side. However, even by wrapping the seal tape in this manner, gaps can form in the connecting portion so that gas in the container 1 leaks.
Then, in the case where gas has leaked from the connecting section in this way, the gas is detected on the sucking side, so that even though liquid still remains inside the container 1, the container 1 is judged to be empty. Consequently, the container 1 with liquid still remaining is exchanged for a new one with liquid stored therein, being extremely uneconomical.
In addition, when the siphon tube 4 is connected to the plug 3, the seal tape is wrapped around the external thread of this siphon tube 4 as mentioned above, and an O-ring or the like must be inserted, so that this connecting operation requires a great deal of time and effort.
Consequently, it is an object of the present invention to provide a connector that reliably prevents leakage of gas when drawing out a liquid, thus eliminating erroneous detection of empty containers, and enabling the liquid inside the container to be used efficiently.
The connector of the present invention is one comprising a plug fitted to an opening portion of a container that stores a liquid, and a socket for connection to the plug; and is characterized in that the plug has, a lid body secured in a fluid tight manner to the opening portion, a plug portion provided on the lid body and connectable to the socket, and a siphon tube extending downward from a lower portion of the lid body such that when the lid body is secured to the opening portion a lower end is arranged near a bottom of the container, and the siphon tube comprises a tube integrally formed with the lid body.
According to the present invention, the tube which extends downward from the lid body and which delivers the liquid in the container is integrally formed with the lid body secured to the opening portion of the container to thus constitute the siphon tube. Therefore, when the socket with the connected hose is connected to the plug portion and the liquid inside the container is drawn out by the pump, the undesirable situation where gas leaks from the siphon tube can be reliably prevented. Accordingly, problems where due to gas leaking, there is erroneous detection that the container is empty and hence the container with remaining liquid is exchanged for a new one, can be reliably prevented. That is, it is possible to completely use up the liquid without any liquid remaining inside the container, thus being extremely economical.
Moreover, because the siphon tube and the lid body are integrally formed, then in comparison to the case where a separate tube is connected by screwing into the lid body, the complicated connection operation can be eliminated.
In addition, the connector of the present invention is one comprising a plug fitted to an opening portion of a container that stores a liquid, and a socket for connection to the plug; and is characterized in that the plug has, a lid body secured in a fluid tight manner to the opening portion, a plug portion provided on the lid body and connectable to the socket, and a siphon tube extending downward from a lower portion of the lid body such that when the lid body is secured to the opening portion a lower end is arranged near a bottom of the container, and the siphon tube comprises a tube integrally formed with the lid body and an extension tube abutted against an end of the tube body with the abutting portions welded together and integrated in a fluid tight manner.
According to the present invention, the siphon tube comprises the lid body secured to the opening portion of the container, the tube integrally formed with the lid body, and an extension tube welded to this tube and integrated in a fluid tight manner. Therefore, when the socket with the connected hose is connected to the plug portion and the liquid inside the container is drawn out by the pump, the undesirable situation where gas leaks from the siphon tube can be reliably prevented. Accordingly, problems where due to gas leaking, there is erroneous detection that the container is empty and hence a container with remaining liquid is exchanged for a new one can be reliably prevented. That is, it is possible to completely use up the liquid without any liquid remaining inside the container, thus being extremely economical.
In addition, because the tube and the extension tube are integrally formed by welding, then in comparison to the case where this is connected by screwing and securing the tube to the internal thread of the lid body, leakage from the connecting portion can be reliably prevented.